1. 1. Dr. Omneya Nagy Elmakhzangy Special Fetal Care Unit Ain Shams University Member of EFMF
2. 2. 3D and 4D scanning It is the process of creating a 3D visual presentation of parameters of interest. The main principle behind this is "planar geometric projection" i.e a 2D image to represent the 3D data the third dimension impression is acquired through online rotation of the image along X , Y and Z axis.
3. 3. Voxel and Pixel
4. 4. Imaging practitioners routinely use cross- sectional planar ultrasonographic information to develop a three-dimensional (3D) mental concept of anatomy. With three-dimensional ultrasonography (3DUS), any desired plane through a pelvic organ can be obtained, regardless of the orientation of the sound beam during acquisition.
5. 5. With 3D or volume ultrasonography, a volume (rather than a slice) of ultrasonographic data is acquired and stored. The stored data can be reformatted and analyzed in numerous ways; navigation through the saved volume can show innumerable arbitrary planes. In the multiplanar display, 3 perpendicular planes are displayed simultaneously. This will further expand the ability to show complex anatomic relationships
6. 6. Normal uterus. A multiplanar display shows the axial view (A), the midsagittal plane (B), and the true midcoronal plane (C). Depiction of the true midsagittal and midcoronal planes is achieved by correlation between the 3 planes. The midcoronal view (C) clearly shows the normal external fundal contour of the uterus and the normal triangular shape of the endometrial cavity.
7. 7. Clinical Applications
8. 8. Uterus
9. 9. Normal uterus Logic question : why cant we usually obtain a coronal section in a 2D scan? Answer: you have to options to scan the uterus either transabdominaly and in this case the sides of the bony pelvis will prevent scanning through pelvic side walls , transvaginally and this is limited by the physical limitation in moving the probe within the boundaries of the vagina .
10. 10. The normal uterus, as seen in the coronal plane, has a flat or slight upwardly convex fundal contour. The endometrium is normally approximately triangular, the top of which is flat or minimally concave toward the lumen . The echogenicity of the endometrium varies during the cycle but is generally more echogenic than the myometrium. The normal endometrium should have a homogeneous echo texture, and the endometrial-myometrial junction should be distinct. The cervical canal is seen as a tubular echogenic structure extending inferiorly from the lower endometrial cavity. The contour of the cervix is well shown in the coronal view
11. 11. Uterine or Mullerian Anomalies According to American Fertility Societys scheme, there are 7 classes of anomalies: class 1 : segmental agenesis or hypoplasia; class 2 : unicornuate uterus. class 3: uterus didelphys; class 4: bicornuate uterus; class 5: septate uterus; class 6: arcuate uterus class 7: diethylstilbestrol-related anomalies.
12. 12. Class 1 The unicornuate uterus is essentially half a uterus didelphys with a single hemiuterus deviated to the right or left of the midline, showing only a single cornual angle. The diagnosis of unicornuate uterus is very difficult to confirm with 2DUS because the findings are subtle. The nulliparous unicornuate uterus is somewhat smaller than normal and deviated from the midline. The multiplanar capability of 3DUS permits confident demonstration that there is only 1 cornual angle
13. 13. Unicornuate uterus. A multiplanar display of the left unicornuate uterus is shown. This diagnosis is difficult to establish with 2DUS because the uterus may appear grossly normal or slightly laterally deviated. With 3DUS, the diagnosis is confidently made because the coronal plane (C) shows clearly that there is only a single cornual angle
14. 14. Class 2 The uterus didelphys consists of 2 distinct and separate uterocervical cavities. The 2 fundi are widely separated and may not be completely imaged on any single planar image. The cervices are adjacent to each other, but the cervical canals are distinct
15. 15. Uterus didelphys. A composite of a multiplanar display (AC) of the uterus and a coronal image of the cervix (D) from another volume is shown. The axial plane (A) shows 2 widely separated hemiuteri, typical of this malformation. The sagittal plane (B) is between the 2 hemiuteri and therefore shows very little. The coronal plane (C) shows the widely separated fundal regions (arrows); the lower uterine segments and the cervical canals are closely apposed.
16. 16. Class 3 The bicornuate uterus has a midsagittal cleft or indentation in the external contour of the fundus of at least 1 cm in depth . In addition, the uterine cavity is divided by a septum that extends caudally for a variable extent. The cervix of the bicornuate uterus may be single or double.
17. 17. Bicornuate unicollis uterus. This coronal view shows the deep (>1-cm) midline sagittal groove (arrows), which characterizes this type of uterine anomaly. In this case, a single cervical canal is shown; however, a bicornuate uterus may have 2 cervical canals.
18. 18. Class 4 The septate uterus, the most common uterine anomaly, usually has a normal external fundal contour but may have a shallow fundal indentation measuring no more than 1 cm in depth .
19. 19. Septate uterus. A composite of a multiplanar display (A, axial; B, sagittal; C, coronal) and a rendered image of the endometrial cavity, extracted from the uterus (D), is shown. Note that the septum is relatively long and thin and extends down to the level of the cervix (thin arrow). The external contour of the uterine fundus is shown in the coronal plane (C) as smooth, indicating a septate and not a bicornuate uterus.
20. 20. Class 5 The cavity of the septate uterus is divided partially or completely by a septum of variable thickness. If the septum does not extend down to the uterine isthmus (the level of the internal cervical os), the malformation is termed a subseptate uterus.
21. 21. Subseptate uterus. Three-dimensional multiplanar sonohysterography shows a normal external uterine contour. The coronal plane is ideal for precise definition of this uterine malformation. This is a subseptate uterus because the septum extends caudally to the lower uterine segment but not to the internal os. The addition of fluid helps outline the extent of the septum and exclude other intracavitary abnormities
22. 22. Class 6 The arcuate uterus has a normal external fundal contour but an inner fundal contour abnormality in which the fundal myometrium is convex toward the uterine lumen. This convex myometrium should not exceed a height of 1 cm when measured from the cornual angle . The actual prevalence of the arcuate uterus is unknown because the subtle abnormality is easily missed without visualization of the coronal plane. The clinical importance of this mild abnormality is uncertain, although this lesion is generally thought of as less problematic than the septate uterus
23. 23. The coronal view, obtainable only with 3DUS, can directly visualize the endometrial and fundal contours, ruling out the diagnosis of a subseptate uterus and confirming a positive diagnosis of an arcuate uterus.
24. 24. Class 7 The diethylstilbestrol-related uterus has a hypoplastic cavity with variable deformity of the shape of the uterine cavity .The external uterine contour is normal, but the uterine cavity is smaller than normal and has been described as T shaped. Constriction bands occur in the upper uterus, resulting in bulbous cornual regions and a deformed uterine body. The lower uterine segment may be widened but more often shows severe stenosis.
25. 25. T-shaped uterus. Multiplanar and rendered views were acquired during 3D sonohysterography.
26. 26. Intracavitary lesions
27. 27. Endometrial polyp
28. 28. Composite findings of a subseptate uterus with multiple enodmetrial polyps
29. 29. Endometrial calcification and a small submucpus myoma, This technique of manipulating the multiplanar display and correlating the findings in all 3 planes is used to confirm the location of a lesion, to show that a finding is real rather than artifactual, or to show that a true midsagittal or midcoronal plane has been obtained.
30. 30. Intrauterine contraceptive device .This coronal view, obtainable only with 3DUS, assists in precisely localizing the device within the uterine cavity. The IUD is shown to be slightly caudal to the fundal myometrium, which is convex toward the lumen in this subtle uterine anomaly. However, the IUD is entirely within the endometrial cavity without evidence of myometrial penetration
31. 31. Uterine synechiae
32. 32. Myometrium Uterine myomas can be assessed by 3DUS. The multiplanar display, especially the coronal view, allows precise localization of a myoma with respect to the endometrial cavity. Precise localization of uterine myomas assists in determining the surgical approach (hysteroscopic resection or abdominal myomectomy).
33. 33. Intracavitary myoma and endometrial polyp. Three-dimensional multiplanar sonohysterography shows a round mass, which is isoechoic with the myometrium and almost completely surrounded by fluid. This intracavitary myoma (m) is deemed amenable to hysteroscopic resection. In addition, there is a more echogenic, smaller endoluminal mass representing a polyp (p).
34. 34. Cystic adenomyoma. A composite of a multiplanar display of the uterus (AC) and another oblique coronal plane through the uterus (D) is shown. There is a cystic mass in the right side of the uterus containing uniform low-level echoes and surrounded by myometrium. The initial differential diagnosis included a left unicornuate uterus with an atretic rudimentary right horn. Three-dimensional ultrasonography was useful in showing the exact midcoronal plane through the endometrial cavity (C). The cavity is shown to be triangular in shape with 2 cornua (arrows), excluding a unicornuate uterus. A, Axial view through the uterus showing the cystic mass on the right. B, Sagittal view of the uterus at the level of the endometrium. C, View through the midcoronal plane of the endometrial cavity. D, Oblique coronal view through the long axis of the cystic mass, which best shows the normal fundal contour of the uterus and the rim of myometrium surrounding the mass.
35. 35. Locating Early Gestational Sac
36. 36. Ovaries and adenxae
37. 37. Multicystic ovarian mass
38. 38. For assessing the patency of the fallopian tubes, x- ray HSG and laparoscopy are still the most widely used methods. Recently, ultrasonography with fluid as a contrast agent (ie, sonohysterography) has been used in the diagnosis of tubal patency or blockage. On 3DUS, the entire tube can be evaluated because a volume of data rather than a single slice is saved and reviewed later from any arbitrary plane.
39. 39. This method appears to have advantages over the conventional hysterosalpingo-contrast ultrasonographic technique, especially in terms of visualization of a spill from the distal end of the tube, which is achieved twice as often with the 3D technique. The mean duration of the imaging procedure is shorter with 3D , but the operator time, which includes postprocedure analysis of the stored information, is similar. A considerably lower volume of contrast medium is used for 3D PDI in comparison with that used for conventional 2D hysterosalpingo-contrast ultrasonography
40. 40. Fallopian tubes. 3D HyCoSy (Hysterosalpingo Contrast Sonography)
41. 41. Basal Ovarian Volume and AFC in infertility cases Three D ultrasound is more accurate in determining ovarian volume using the Virtual Organ computer- aided Analysis (VOCAL, GE Kretz) technique . This technique employs a rotational method which involves the manual delineation of the ovarian volume throughout several planes as the data set is rotated through 180 degrees in a consecutive series of rotations ( angle dependant on number of planes chosen could range from 6 to 30 ) , until a calculated volume is generated
42. 42. Antral follicular Count and folliculometry Number of follicles at the early follicular phase has been reported to be a good test for prediction of ovarian response (Kwee 2007, Jayaprakasan 2008) . All follicles < 10mm are measured using 2D ultrasound in the longitudinal and transverse planes, however 3D techniques are now available for automatic calculation (SonoAVC) (Raine-Fenning 2008).
43. 43. Folliculometry A new automated ultrasound software technique has recently been developed which relies on volume calculation using 3-dimensional VOCAL technique and on colour coding of each follicle (SonoAVC, GE ) (Raine Fenning 2008). A 3D volume is obtained of the stimulated ovary, and using the software will give mean diameter and volume of the hypo echoic areas within the ovary representing the follicles, it will then colour code each follicle differently allowing studying each one separately .
44. 44. Endometrial Receptivity Endometrial receptivity is defined as a temporary unique sequence of factors that make the endometrium receptive to the embryonic implantation.
45. 45. Optimal conditions of implantation could be:- Endometrium > 7 mm, Endometrial volume > 2 ml Hypoechogenic endometrium with 3 well delinated layers, Uterine PI < 3, Presence of sub-endometrial vascular flow. High VI,FI&VFI in endometrial & sub- endometrial zone.
46. 46. uterine artery Doppler (PI=3.16). uterine artery Doppler (PI=1.15).
47. 47. 1- VI (Vascularization index): Vascularization index is the ratio of the number of color voxels (volumetric pixel) to the total number of voxels in the sampled tissue, thus it represents the percentage of vascularized tissue
48. 48. 2- FI (flow index) : Flow index is the average colour value of all colour voxels and it describes the mean velocity of flow in the sampled tissue.
49. 49. VFI (vascularization flow index) : is the average colour value of all colour and grey voxels and describes both: the vascularization and the blood flow.